Dimethyl carbonate as a green organic modifier in supercritical fluid extraction of pesticide residue analysis in apple samples.

In line with the Green Analytical Chemistry principles, the drive to replace conventional organic solvents with more sustainable alternatives is rapidly evolving. This study introduces dimethyl carbonate (DMC) as a novel co-solvent in supercritical fluid extraction (SFE) for the multi-residue analysis of pesticides in apple samples. The extraction performance of DMC was systematically compared with that of acetonitrile (ACN) and bio-ethanol (EtOH) under optimized conditions (30% co-solvent, 150 bar, 70 °C, 1 mL min-1 flow rate, and 21 min of total extraction time). A panel of 64 pesticides, covering different chemical classes (e.g., organochlorine, organophosphorus, pyrethroid, carbamate, benzamides, triazoles), polarities (with log kow ranging from -0.9 to 7.7), and molecular weights (ranging from 141 to 532), were evaluated. The method achieved an average extraction yield of 85% with DMC, while also providing significantly cleaner extracts by reducing the co-extraction of matrix components. These results underline the potential of DMC to enhance the sustainability and efficiency of pesticide residue analysis, closely aligning with the objectives of green analytical practices.